
\begingroup
\centering
\begin{tabular}{lcccc}
   \toprule
    & \multicolumn{2}{c}{\makecell{Patents \\ (mean = 2.24, sd = 1.69)}} & \multicolumn{2}{c}{\makecell{Breakthrough patents \\ (mean = 0.26, sd = 0.44)}}\\
\cmidrule(lr){2-3}  \cmidrule(lr){4-5}
                                   & (1)           & (2)           & (3)           & (4)\\  
   \midrule 
\multicolumn{2}{l}{\textit{Panel A: Least-squares estimates}} &  \multicolumn{3}{c}{}\\ \cmidrule(lr){1-5}
   Surname fractionalization index & 0.124$^{**}$  & 0.123$^{**}$  & 0.041$^{***}$ & 0.040$^{***}$\\   
                                   & (0.057)       & (0.053)       & (0.014)       & (0.013)\\   
   Population                      &               & -0.011        &               & -0.009\\   
                                   &               & (0.056)       &               & (0.016)\\   
    \\
\multicolumn{2}{l}{\textit{Panel B: Reduced-form estimates}} &  \multicolumn{3}{c}{}\\
\cmidrule(lr){1-5}
   Predicted surname fractionalization index & 0.030         & 0.034         & 0.019$^{**}$  & 0.020$^{**}$\\   
                                             & (0.035)       & (0.038)       & (0.008)       & (0.008)\\   
   Predicted population                      &               & 0.042         &               & 0.010\\   
                                             &               & (0.053)       &               & (0.011)\\   
\\
\multicolumn{2}{l}{\textit{Panel C: Instrumental-variable estimates}} &  \multicolumn{3}{c}{}\\
\cmidrule(lr){1-5}
   Surname fractionalization index       & 0.416         & 0.491         & 0.261$^{**}$  & 0.249$^{***}$\\   
                                         & (0.499)       & (0.453)       & (0.098)       & (0.078)\\   
   Population                            &               & 0.019         &               & -0.003\\   
                                         &               & (0.061)       &               & (0.014)\\   
\\
   Sanderson-Windmeijer \textit{F}-stat  & 17            & 32; 84        & 17            & 32; 84\\  
\\
\multicolumn{2}{l}{\textit{Panel D: First-stage estimates}} &  \multicolumn{3}{c}{}\\
\cmidrule(lr){1-5}
& \multicolumn{2}{c}{Surname fractionalization index} & \multicolumn{2}{c}{Population}\\
\cmidrule(lr){2-3}  \cmidrule(lr){4-5}
   Predicted surname fractionalization index & 0.072$^{***}$ & 0.077$^{***}$ &  & -0.190$^{***}$ \\
                                             & (0.017)       & (0.018)       &  & (0.070)        \\
   Predicted population                      &               & 0.052$^{*}$   &  & 0.870$^{***}$  \\
                                             &               & (0.029)       &  & (0.106)        \\
    \\
   Inventor fixed effects          & $\checkmark$  & $\checkmark$  & $\checkmark$  & $\checkmark$\\   
   Period-State fixed effects      & $\checkmark$  & $\checkmark$  & $\checkmark$  & $\checkmark$\\   
   Observations                    & 209,944       & 209,944       & 209,944       & 209,944\\  
   \bottomrule
\end{tabular}
\par\endgroup


